There are plenty of online articles about how to introduce kink into a relationship. This AITA Reddit post, featuring a man behaving like a toddler in a supermarket, reads like a great example of how not to do it. Admittedly, it’s not entirely clear if it is a kink thing. It could also be a mental health crisis. However, given he seems to be able to turn it on and off, only directs the infantile behavior towards his wife, and accused her of being judgmental about it, my guess would be it’s a very badly handled big / little kink. That’s a pretty specialized interest, and having a meltdown in a supermarket over a “CHOCWIT ICE CWEAM” is a non-optimal way to involve a partner in it. Although I guess it could be worse. He could have been demanding a diaper change.
This ABDL image is from the Allerted Universe whose Patreon you can find here.